Composition for making glass.



an a. j

= NY ASSIGNOR TO THE FIRM 0F SCHOTlI. & GENZ, OF

mam, eaamam.

COMPOSITION FOR MAKING- GLASS.

No Drawing.

To all whom it may, concern: v

Be it known that I, Orro Sonorr, a 01th zen of the German Empire, residing at Jena,

cost of production and of the same general applicability.

In consequence of this property the new kind of glass is particularly suitable for chemical apparatus and for gage-glasses.

In the kind of glass according to the present invention at least 50 per cent. of silicic acid is made use of as in well-known kinds of glass. Besides the said silicic acid the new glass further contains alumina 4 to 15 per cent., lime 3 to 11 per cent., boracic acid 5 to 15 per cent. and alkali 4 to 14 percent. The percentage of alumina and lime together however must amount to not less than half and not more than five times the percentage of the boracic acid. While no other glassforming components are employed for the new kind of glass, of course the addition of a small quantity of one or more other substances having some such secondary purpose as a coloring of the glass is not excluded.

Soda is suitable as the alkaline compon nt.

Bpeelflcation of Letters intent.

well within the limits given Patented ar.9, 1915.

Application filed September 12, 1912. Serial No. 719,977.

Accordingto the experience gained, when Working out the invention, the new kind of glass displays a particularly great capacity of resisting chemical action, when in the choice of the amount of amount of alumina these amounts are kept above, 0., when with a proportion of soda of 8 to 12 per cent. not less than about 6, but also not more than about 12 per cent. of alumina are taken.

I claim: I

1. Glass containing at least 50 per cent. silicic acid and having as its other glass forming components alumina i to 15 per cent., lime .3 to 11 per cent., boracic acid 5 to 15 per cent. and alkali 1 to 14 per cent.,

the total percentageof alumina and lime being at least half and at most five'tlmes that of the boracic acid. i

2. Glass containing at least 50-per cent. silicic acid and having as its other glass forming components alumina 6 to 12 per cent., lime 3 to 11 per cent., boracic acid 5. to 15 percent. and soda 8 to 12 per cent., the total percentage of alumina and lime being at least half and at most five times that of the boracic acid.

OTTO SCHOTT.

Witnesses: r

,. PAUL Kniienn,

RICHARD n.

soda and of the 

